Effects Of Ultrasound-guided Settatus Plane Block On Post-mastectomy Pain Syndrome After Modified Radical Mastectomy

Objective: to investigate the effect of ultrasound-guided anterior serratus plane block on perioperative analgesia in patients with modified radical mastectomy(MRM)and to explore its role in preventing post-mastectomy pain syndrome(PMPS)and improving long-term prognosis.Methods: one hundred female patients scheduled for elective unilateral modified radical mastectomy from the First Affiliated Hospital of Chongqing Medical University from May to July 2018,aged 28 to 75 years,American society of anesthesiologists physical status I or II,were randomly divided into 2 groups using a random number table method:serratus plane block combined with general anesthesia group(GB)and control group recieved a mock block with normal saline(G).Before induction of anesthesia,patients in the GB group were injected with 0.33%ropivacaine for 30 ml in the serratus anterior plane under ultrasound guidance.Group G patients were injected with the same amount of saline at the same location.Patients in the two groups underwent tracheal intubation,followed by static suction combined anesthesia.Patients in both groups were given patient controlled intravenous analgesia(PCIA)after surgery.The times of effective delivered doses 48 h after operation,the cases of remedial analgesia were recorded.Numreical rating scale(NRS)was used to evaluated the pain relief at 4h,12 h,24h,48 h postoperative and at 3,6,9,12 months postoperative in both groups.PMPS incidence and the 40-item Quality of Recovery Score(QoR-40)will also be recorded.Results:(1)The acute NRS scores both at rest and movement of the GB group were significantly lower than that of the G group at 4 h,12 h,24 h,and 48 h postoperative(P<0.05).(2)The number of effective analgesia pump pressing within 48 h after operation and the remedial analgesic cases in the GB group were significantly less than that in the G group(P<0.05).(3)The incidence of PMPS in GB group was significantly lower than that in the G group at 6 and 9 months postoperative(P<0.05).(4)The NRS scores in the GB group at 6 and 9 months postoperative were significantly lower than those in the G group(P<0.05).(5)There was a correlation between the acute NRS scores and the chronic NRS scores in all patients(P<0.05).(6)GB group had higher QoR-40 scores than G group at 3 months postoperative(P<0.05).Conclusion:Ultrasound-guided serratus plane block applied to modified radical mastectomy for breast cancer can not only improve acute pain scores,reduce perioperative opioid consumption,but also reduce the incidence and severity of PMPS,and can also improve early quality of life.In addition,the postoperative acute pain NRS score was related to the severity of PMPS.